IMO the role of stamina just shows how much time your guys can perform well on the floor. If I have like two SGs of comparable talent(for example), i would just put one starter, and one backup, and stamina problem solved(ofc, that's my opinion).
Considering two teams have the same skills, but one team has better stamina, how much would be the difference?
to answer the original question, with the exact same players, perhaps better stamina would win.
Can you get two pops in two weeks in stamina? Most of players got a pop last week in stamina, so I wonder if it's worth to keep stamina training with week too.
One of my trainees popped three consecutive weeks in RB(some elastic effect may be involved her but still), it could happen with stamina too